Tool retainer



y 1932. c. A. BERKEBAK 1 1,858,476

TOOL RETAINER Filed April 25. 1929 CAT'I,

n #2. mmw

Patented May 17, 1932.

UNIT

PAT ICE CHRISTIAN-A. BIRKEZBAK, or DETROIT, MICHIGAN, ASSIGNOB. To EX-CELL-O AIRCRAFT Ann TooI. CORPORATION, or DETROIT, MICHIGAN, A CORPORATION or MICHIGAN TooL RETAINER Application filed. April 25,

The present invention relates to improvements in retainers for tools, such as punches, dies and the like, and is particularly applicable to heavy duty tools adapted for use in metal forming operations. 7

Tools of this character and the retaining means therefor in many instances are subjected to severe operating conditions. Thus, in punching metal of substantial thickness,

10 a heavy force is applied to the punch to shear the metal, and a still greater force is required to withdraw the punch. The 'force required increases as the shearing clearance between the punch and the die is increased for greater thicknesses of metal, and is greater in hot shearing than in cold shearing.

The tools must be removable from. the retaining means so as to permit replacement because of wear or changes in the character 2@ of the work to be performed. To this end, the retaining means must be provided with a suitable lock for holding the tools in position during operation, and for releasing the tools when desired. i

It will be evident that the retaining means and particularly the lockshouldv hold the tool firmly in place, without lost motion, during the operation, and should be of sufiicient A strength to withstand the severe forces imposed thereon. Heretofore, serious diflieul-,

ties have been met with in this regard. In various prior retainers, the tools are not held securely in position, and the. locks tend to crush or shear. Registration between the looks and the coaeting parts on the tools is not accurate or positive,'is difiicult to effeet when assembling the parts, and permits lateral play. In some instances. the locks also tendto injure the tools, and do not per- 40 mit ease of replacement or substitution.

The primary objects of the present invention therefore reside in the provision ofa new and improved toolretainer in which the tool may be readily inserted and removed when desired, which serves to hold the tool securely in position, and which is capable of withstanding the forces imposed thereon.

Further objects reside in the provision in a tool retainer of novel lock means which does not act directly against the shank of 1929. Serial Nb. 357,900.

tain a positive registration and will not injure the punelror cease to be efieetive. I

Another ob ect is to provide lock means of the foregoing character the coacting parts of which on the retainer properand the tool shank may be readily replaced when worn.

A general ob ect resides 1n the provislon of a tool retainer which is simple and relatively inexpensive in construction, and which can be made with simple and easy machine operations. I 7

Further objects and advantages will becomeapparent asthe description proceeds.

In the accompanying drawings, Fig. 1 is a plan view partially sectioned along line l-l of Fig. 3 of a punch retainer embodying the features of my invention.

Fig. 2 is a horizontal sectional view taken along line 22 of Fig.- 3.

Fig. '8 is a vertical sectional. view taken along line 33 of Fig. 1-.

Fig. 4 is a vertical sectional view taken along line 4.-4 of Fig. l. p

Fig. 5 is a transverse sectional view of a punch constituting a part of a modified form of my invention.

F ig.'6 is a fragmentary side viewof'the punch shown in Fig. 5.

Fig. 7 is, a fragmentary sectional view taken along line'77 ofFig. 5. 1

Fig. 8 is a'fragmentary sectional view of another modified form of the invention.

Fig. 9. is a fragmentary sectional view taken at rightanglesto the view in Fig. 8.

lVhile the invention is susceptible of various modificationsand alternative constructions, I have shown in the drawings and will herein describedindetail the preferred embodiment, but it is to be understood'that I do not thereby intend to limit the invention to the specific form disclosed, but intend to cover all modifications and alternative constructions falling within the spirit and scope of the invention as expressed in the appended claims.

.Referring more-particularly to the drawings, I have shown the invention embodied in a punch retainer, but it is to be understood that the invention is applicable to various types of tools.

Referring first to Figs. 1 to 4, the punch retainer comprises a socket member 10 which preferably is cylindrical in form, and which is formed with a central axial recess 11, preferably a bore, extending therethrough. The

bore 11 is adapted to receive the cylindrical shank 12'of a tool, such as the punch 13, with a close sliding fit. The socket member 10 is suitably mounted in a supporting member 14, and in the present instanceis formedonits inner end with a peripheral flange 15 seating ina notch 16 in the upper endlof the member. A suitable backing plate 17. also is disposed in the notch 16 against the upper end of the socket member 10, and projects slightly above the supporting member 14. The supporting member 14, with the socket member 10 and the plate 17 mounted therein,'is removably secured, as by means of bolts 18-, to a base 19'forming part of the operative element of the machine (not shown). It will be evident that when the member 14 is removed from the base 19, the socket member. 10 can be removed therefrom, and that when the member 14 is secured to the base 19, the socket member and the plate 17 are clamped tightly in position. The. base 19 and the plate 17 are formed respectively with registering openings 20 and 21 aligned with the shank 12.

Releasable means is provided. for locking the shank 12 securely against the backing plate 17. To this end, the socket member. 10 is formed with alongitudinalkeyway 22along the bore 11. The keyway 22 opens to the ends of the member 10 and'also to the bore 11. dinalkey23 having a snugsliding fit in the keyway 22. The key 23 maybe-secured to the shank 12 in different ways. In Figs. 1 to 4, a'transverse notch 24 ismilled in one side of the upper end of the shank 12 substantially to the center. In this instance, the key 23 is in the form of aplate backing against the root surface and snuglyconfined between the side surfaces of the notch 24, and is suitablyv secured inposition by a rivet 25. The key 23 extends substantially through the notch 24, and one end projects therefrom :into the keyway 22. It will be evident that the key 23 is held securely against en'dwise movement or play, and that it can be removed-and replaced when worn without scrapping of the tool. The projecting face 26 is substantially radial,and coacts with the adj acentface 27 of the k-eyway 22 to positively and accurately locate the tool peripherally without regard to whether ornot the other face of the key is mutilated. Registration is easily and definitely effected.

A locking member, preferably in the form of alhall 28..is arranged in wedging engage- Secured to the shank 12 is a longituupward thrust. During the face 30'of the key 23. One end of the bore 29 opens to the upper or inner end surface of the socket member 10, and the other end opens partly to the bore 11 and partly to the keyway22. A coil spring 31 is disposed in the bore 29'between the backing plate 17 and the ball 28 in abutting engagement therewith,.and serves to urge the ball 28 against the key 23. The outer end of the bore 29 also opens throughan aperture 32 to the outer end surface of the socket member 10, this aperture permitting the insertion of a suitable tool (notshown) for raising the ball 28 out of engagement with the key 23 when it is desired to remove thepunch. While the relative inclination between the key and the bore 29, represented'by thecharacter6, is not closely fixed and. may be varied within reasonable limits, preferably the angle 0 is between 12 and 16 degrees.

Obviously, the notch 24 permits the ball 28 to project partlyinto the bore 11 for engagement with the key 23. To increase the possible rangeof engagement, the upper end of theshank 12 above the key. 23- and next to the bore 29 is notched or'cut away asindicated at 33. By. reason of thisiconstruction, the wedging force is applied approximately at or within the circumference: of the shank12, anda relativelylarge ball 28 may be usedI The rear face 30 ofthe key 235 is formed with a straight longitudinal groove 34 conforming laterally substantially to i the curvature of the ball 28 and constituting-a raceway therefor. The groove 34 is inclined downwardly. and inwardly into the key'23 at an angle slightly'less than the angle 6- so that its surface is still'slightly inclined into the path of the ball. 28.. This inclination is represented by the angle qS which preferably is'between 2 and 3 degrees.

In operation, the backing plate 17'takes the downward thrust, the ball28 wedges tightly against the key 23 thereby holding'the shank 12 securely against outwardmovement. The tools 13 can be removedeasily and quickly byrais ing the ball 28 out of locking position.

It will be evident that the construction is simple and inexpensive, and that the manufacturing operations therefor. are easy. Simplemilling operations will serve to'form the notches 16 and.33 and the groove 34. The angular bore 29 needfnot be perfect, or 10- catedwith great nicety relative to the shank 12 since it is not relied upon to locate the latter peripherally. At the same time the construction is compact, sturdy, efficient and not easily damagedi A large ball 28'may be provided: without substantially increasing the WVhen the key 23 is worn or mutilated, it can be replaced by anew key, thereby increasing the life of the tool 13.

The form of the invention shown in Figs. 5, 6 and 7 differs from the first form only in the manner in which the key 23 is mounted on the shank 12, and hence corresponding parts erence characters. In this form, the upper end of the shank 12 is formed with a longitudinal groove 35 in which the key 23 is snugly disposed. Projecting laterally into a bore 36' in the upper end of the shank 12 and across the top of the key 23 is a pin 37 for holding the key in position. The projecting end of the pin 37 is milled down to less than the thickness of the key 23, and the upper end of the latter is curved to conform to the pin. The sides of the groove 35 are milled partially away, as indicated at 38 and 39, to provide clearance and in one instance to expose more of the key 23 to the ball 28. Preferably, the key 28 and pin 37 are welded to each other, and also to the shank 12 asindicated at 40.

The form of the invention illustrated in Figs. 8 and 9 is generally similar to the first forms, and corresponding parts thereof are therefore identified by the like reference characters. In this form, the key 23 is secured in a longitudinal groove 41 in the shank 12. The bore 29 does not open to the central bore 11, but only to the keyway 22. Hence, the en tire locking action occurs outside of the bore 11.

I claim as my invention:

1. Atool retainer comprising, in combination, a socket member having an aperture adaptedto receive a tool and having an elongated key-way opening to said aperture along one side thereof, a tool having a sliding fit in said aperture, an elongated longitudinal key rigid on said tool and having a sliding fit in said key-way, and spring-pressed wedge means projecting into said key-way and coacting'with said key to prevent withdrawal of said tool from said aperture.

2. A tool retainer comprising, in combination, a socket member having an aperture adapted to receive a tool and having a keyway opening to said aperture along one side thereof, a tool having a sliding fit in said aperture, a key rigidly secured to said tool g3 and having a sliding fit in said key-way, said of the two forms are identifidby like refkey being formed with a wedge surface, and a spring-pressed ball projecting into said key-wayandengaging said surface to exert a wedging, action thereon whereby the tool is held against withdrawal from said aperture.

3. A tool retainer comprising, in combination, av socket member having an elongated aperture, having a key-way opening tosaid aperture longitudinally thereof, and having a second aperture inclined to said key-way and opening thereto, a tool slidably disposed in said first mentioned aperture, abutment means disposed at one end of said first mentioned aperture to substantially define the innermost position of said tool, a key rigidly secured to said tool and projecting laterally therefrom into said key-way, and a springpressed ball in said last mentioned aperture projecting partially into. said key-way into wedgingengagement with said key to prevent withdrawal ofsa-id tool from said first mentioned aperture.

l. A tool retainer comprising, in combination, a socket member having a central bore, having a spline key-way opening to said bore longitudinally thereof and having an inclined recess'opening to said key-way, a. tool dis posed in said bore, a key extending longitudinally on said tool and projecting slidably into said key-way, said key being formed with a. wedge surface inclined into said recess, and a spring pressed ball in said recess engagi-ng said surface.

5. A tool retainer comprising, in combination, a socket member having a central aperture, a spline key-way opening to one side of said aperture and longitudinally thereof, and an aperture inclined downwardly towards-said keyway and opening thereto, a tool disposed in said central aperture, a flat key rigidly securedtoand projecting from said tool into 'saidkey-way, said key being formed with a wedge surface inc-lined downwardly into the line of said inclined aperture,'a ball disposed in said inclined aperture in wedging engagement with said surface, and spring means acting on said ball to urge the latter downwardly, whereby said key is clamped against one side of said keyway to effect peripheral location of said tool, and whereby said tool is held against withdrawal from saidcentral aperture.

6. A tool retainer comprising, in combination, a socket member having a cylindrical tool receiving bore, a cylindrical tool portion disposed in said bore with a sliding fit, a clamping plate secured to said tool portion and defining a clamping surface extending generally longitudinally of said bore, said member being formed with. a clamping sur face opposed to and slightly inclined longitudinally of said bore relatively to said first mentioned surface, and spring pressed means interposed" between said surfaces and having aw'edg-in'g engagement with said plate.

7 A tool retainer; comprising, in combination, a socket member having a tool receiving'bore andl arecess' opening'to said bore, a tool disposed in said bore with a sliding fit, a clamp'ing member'secure'd to one side of said tool and projecting'into said recess, and having a wedge-surface inclined'to the axis of said bore, said recess defining .a wedge surface inclined to the axis of said bore in the same general direction as but at'a greaterangle than said first mentioned surface, and yielding means removably interposed in wedging engagement between said surfaces.

8. A toolretainer comprising, in combination, a: support having an aperture and forinedwith an elongated stop shoulder longitudin'ally of said aperture, a tool in said aperture, an elongated longitudinal shoulder on said tool extending across said stop shoulder, and means for clamping said last mentioned shoulder against said stop shoulder to effect peripheral location" of said tool in said aperture'iv 9; Atool retainer comprising, in combination, a socket member having a bore and a key-way openingto said bore longitudinally thereof; and an aperture inclined downward- 1y toward :saidkey and opening at its lower end to said key-way-and said bore, a tool disposed in said bore, a clamping'member securedto said tool and projecting laterally therefrom into said key-way-,- said clamping member being formed with a downwardly inclined'groove.substantially arcuate in cross section-and projecting-at an angle into the line-ofsa-id aperture, a spring-pressed ball in said aperture, said ball projecting partially into said key-way and said bore into clamping engagement with the wall of said groove.

10. Atoolretainercomprising, in combination, asupport having a'bore and formed with anelong'ated'stop shoulder longitudinally of said bore, a tool in said bore, an elongated longitu-din'alshoulder on saidtool extending across said stop shoulder, and spring-pressed wedge means for clamping said last mentioned shoulder against said stop shoulder to effect peripheral location of said tool in said bore; 1-1. A tool retainer comprising, in combination, a socket member having an aperture and a key-way opening to said aperture along one side thereof, a tool having'a sliding fit in said aperture, and formed with a recess, a clamping member secured in said recess, said member being formed with a wedge surface, and'a spring-pressed ball projecting into said recess and engaging'said surface to exert a wedgingaction' thereon whereby the tool is held against withdrawal from saidaperture.

12; A tool retainer comprising, in combination, asupport having an aperture therein, -a' toolin said aperture, a wedge member set in said-tool and having a wedge surface, said sup'porthaving an aperture inclined longitudinally of said first mentioned aperture-and openingto said surface, and a spring pressed clamping member-in said last mentioned-aperture' engaging said surface.

13. A tool-retainer comprising, incombination, a supporting member, a socket member removably supportedv in. said supporting member, a; backing plate positioned across thetop of said socket member,"said socketmember'having ai'central axial bore openingtfat itsuppcr end to said backing plate, and having a square key' way opening longitudinally to one side of'said bore, one

side of said key-way, being. radially disposed relative to said boreysaid.socketmembenhav a second bore opening at the top to' said backing'rplate' and at the bottom to said keyway and said bore, atool shank disposed in said first mentioned bore insubstantial end abutting engagement with said backingplate, said shank being formed with a lateral notch substantiallyto the center thereof, a key plate secured in said notch and projecting slidably into said key-way, the'projecting'end of said key being formed with a straight downwardlyland inwardly inclined groove sub' stantially arcuate intlateral cross-section, said groove beinginclined downwardly ata small 'angle into the line of said inclined bore, a balldisposed in the lower end of said inclined bore and projectingipartiallyinto said key-way and said central boreinto wedging engagement with the wall of said groove, and springmeans in saidbore'forYurging-said ball downwardly."

14.- A tool retainer comprising, in combination, a socket member h-avingwa central axial bore, and having square key-way openinglongitudinally to oneside of said bore,one side of said key-waybeingxra'dially disposed relative to said bore, and having a second bo'reinclined downwardly to said key-way,- a tool shank disposed in said bore, a key plate secured in said shank and projecting slidably into said ikQY-WWY, the projecting end of said: key being formed with'a straight downwardly and inwardly inclined groove substantially arcuate in lateral'crosssection, said groove being inclined downwardly at'a small'angle into" the: line of said inclined bore, a: ball disposed in the lower end of said inclined. bore and projecting partially into said key-way and said central bore into wedging. engagement'with the wall of said groove, and springmeansinsaid bore for urging said ball downwardly.

Intestimony whereof, I have hereunto affixed' my signature.

oHRIsTIAN' A. BIRKEBAK; 

